Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

Phd by thesis

Warm mix asphalt: an overview

Performance of Warm Mix Asphalt containing Sasobit®: State-of-the-art

Pavement engineering materials: Review on the use of warm-mix asphalt

Asphalt is the most recycled material in the USA at a re-use rate of 99%. However, by average only 10–20% reclaimed asphalt pavement (RAP) is used in a given mix design and large part of the RAP is degraded for use in lower value applications. The amount of RAP in asphalt mixtures can be significantly increased with the application of good RAP management practice, readily available modern production technologies and advanced knowledge of mix design. This paper summarises the state-of-the-art approaches for increasing the amount of RAP in asphalt mixtures above 40%. The production challenges and common pavement distresses of very high RAP content mixtures are identified and methods to optimise the mix design as well as production technology in order to allow manufacturing of such sustainable mixtures are described. The best practices for RAP management and economic benefits of high RAP use are also discussed.

Review of very high-content reclaimed asphalt use in plant-produced pavements: state of the art

The mechanical performance of a typical surface course mixture, modified with two different plastic wastes, both via the wet and dry processes, was evaluated in this study. Water sensitivit...

Asphalt Surface Mixtures with Improved Performance Using Waste Polymers via Dry and Wet Processes

The environmental concern about waste generation and the gradual decrease of oil reserves has led the way to finding new waste materials that may partially replace the bitumens used in the road paving industry. Used motor oil from vehicles is a waste product that could answer that demand, but it can also drastically reduce the viscosity, increasing the asphalt mixture’s rutting potential. Therefore, polymer modification should be used in order to avoid compromising the required performance of asphalt mixtures when higher amounts of waste motor oil are used. Thus, this study was aimed at assessing the performance of an asphalt binder/mixture obtained by replacing part of a paving grade bitumen (35/50) with 10% waste motor oil and 5% styrene-butadiene-styrene (SBS) as an elastomer modifier. A comparison was also made with the results of a previous study using a blend of bio-oil from fast pyrolysis and ground tire rubber modifier as a partial substitute for usual PG64-22 bitumen. The asphalt binders were tested by means of Fourier infrared spectra and dynamic shear rheology, namely by assessing their continuous high-performance grade. Later, the water sensitivity, fatigue cracking resistance, dynamic modulus and rut resistance performance of the resulting asphalt mixtures was evaluated. It was concluded that the new binder studied in this work improves the asphalt mixture’s performance, making it an excellent solution for paving works.

https://repositorium.sdum.uminho.pt/bitstream/1822/47620/1/2735-applsci-07-00794.pdf

Improving Asphalt Mixture Performance by Partially Replacing Bitumen with Waste Motor Oil and Elastomer Modifiers

The environmental and economic benefits of using Reclaimed Asphalt Pavement (RAP) material in hot mix asphalt (HMA) applications could be pushed up to the limit, by producing totally recycled HMAs (100% RAP), but the performance of this alternative must be satisfactory. In the present study, the utilization of a used motor oil as a rejuvenator was evaluated. This would allow the aged binder to restore some of its original properties, thus promoting an adequate performance of the mixture. After studying the RAP moisture content, the optimal amount of oil was determined by conventional bitumen tests, using the penetration grade as the selection criterion. Then, the binder was evaluated through rheological testing, and laboratory specimens were prepared and tested for water sensitivity, permanent deformation, stiffness and fatigue, in order to confirm that the totally recycled mixture will perform as good as a conventional mixture used for comparison purposes.

Pushing the Asphalt Recycling Technology to the Limit

https://repositorium.sdum.uminho.pt/bitstream/1822/38190/4/2132-Pasandin_et_al_Accepted_Manuscript.pdf

Influence of ageing on the properties of bitumen from asphalt mixtures with recycled concrete aggregates

Several processes and products are available to produce warm mix asphalt (WMA). The use of those may reduce the mixing and compaction temperatures in relation to hot mix asphalt (HMA), ensuring a good performance of the pavement. Lower plant mixing temperatures mean reduction in fuel consumption and lower emissions, what may contribute to diminish odours and health problems. A laboratory study on the properties of the modified binders (using two commercial WMA additives—Sasobit® and Cecabase®) was carried out through conventional (penetration, softening point), dynamic viscosity and rheology (DSR) tests, in order to establish the optimum additive content. Stripping of binder from the aggregates is a reported problem in WMA. Thus, the affinity of the modified binders was assessed without encountering significant problems. It was also observed that only Sasobit® alters the viscosity of the binder. A maximum temperature reduction of 15°C was achieved using 4% of Sasobit® with a softer binder.

https://repositorium.sdum.uminho.pt/bitstream/1822/18677/1/10-RILEM_ATCBM_2009.pdf

Hugo Manuel Ribeiro Dias da Silva

Papers

Asphalt Surface Mixtures with Improved Performance Using Waste Polymers via Dry and Wet Processes

Improving Asphalt Mixture Performance by Partially Replacing Bitumen with Waste Motor Oil and Elastomer Modifiers

Pushing the Asphalt Recycling Technology to the Limit

Influence of ageing on the properties of bitumen from asphalt mixtures with recycled concrete aggregates

Evaluation of the rheological behaviour of Warm Mix Asphalt (WMA) modified binders